This invention relates to a cable tensioning device. More particularly, the invention relates to an electric parking brake cable tensioning device for an automobile.
Heretofore, electrically activated parking brakes have included various gearing systems for advancing and retracting lever arms, pedals and cables. These gearing systems are operated by reversible electric motors through complex electrical switching circuits. The complexity of such systems and in particular with regard to their electrical switching circuits has been due to the requirement of reversing the direction of rotation of the motor to release tension on the cable. Also, electric actuator systems presently available for tensioning a parking brake cable are typically subject to backdriving of the electric motor when the cable is tensioned which imposes large loads on the motor and significantly reduces its useful life. Gearing and switching systems required to avoid such backloading have been bulky, complex and not cost effective.